Sound-deadening device for metallic trolley-tracks.



No. 692,629. Patented ren. 4, |902, A. A. cnsunN. l r 4SOUND DEADENING DEVICE FOR METALLIC TRCLLEY TRACKS.

(Application filed Jufy 11, 1901A) (No Model.)

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AZRO A. COBURN, OF HOIIYOKE, MASSACHUSETTS.

SOUND-DEADENING DEVIACEi FOR METALLIC TROLLEY-TRACKS.

sPEcIFIcATIoN'fOrmmg part of Letters Patent No. 692, 62e, dated February 4, 1902.

Application filed July 11, 1901- To all whom it may concern.-

Be it known that I, AzRo A. COBUR, a citizen of the United States ofoAmerica, residing at Holyoke, in the county of Hampden and State of Massachusetts, have invented new and useful Improvements in .Sound-Deadening Devices for Metallic Trolley-Tracks, of

which the following is a'specilication.V

This invention relates to improvements in metallic tubular trolley-tracks, and particularly to that class thereof in which the trolley-Wheel runways are integral with the body of the tube and are located opposite and parallel with each other on the lower borders of the sides of said body, leaving a slot therebetween for a trolley-hanger, the object being to provide sound-deadening appliances to the wheel-surfaces of said runways and means for suitably securing said appliances in said runways, to the end that metallic or similar hard trolley-wheels may roll silently within said runways and the annoying sound resulting from the rapid movement of one metallic object upon o r over the surface of another be wholly obviated.

In the drawings forming part of this specificatiou, Figure 1 is a perspective view of a piece of metallic trolley-track of the class above referred to having linings applied and secured to the runways thereof in accordance with my invention. Figs. 2 and 3 are sectional views of the runways of the track shown in Fig. 1, illustrating different means for securing noiseless linings therein, as hereinafter described.

Referring to the drawings, A indicates the top,andB B the sides, of the track. The runways thereof are each indicated by C, and E indicates the applied lining of the said runways, hereinafter described. The material applied to said trackA for preventing noise caused by the running of trolley-wheels directly upon the surface of said runways consists of a non-metallic runway-lining E, preferably of wood, firmly secured ktherein and suitably grooved to receive the peripheries of said wheels. Said lining E, as shown in Fig. 1, is secured in said runways by bolts 2, each having a nut on the lower end screwing against the lower side of the runway, or, if preferred, a riveted bolt, as shown in Fig. 3,

'serai No'. 67.882. on man.)

may be employed. In either case the head or upper end of said bolt; or rivet is completely ent on said lining which can be struck by wheels passing over it; but whether the bolt 2 (shown inl Fig. 1) or the riveted bolt 4 (shown in Fig. 3) be used the head thereof within said lining E is buried completely within the latter, as shown in Fig. 1. The bolt-hole for said bolt 2 is counterbored at the upper end to admit the bolt-head, and said counterbored end is solidly plugged, as shown, so that a continuous smooth surface shall be presented, over which the trolleywheels may roll noiselessly. l l

In track and lining constructions for light work the lining E may be secured in the track-runway, in the manner shown in Fig. 2,

by passing an ordinary wood-screw 3 through the runway upwardly into the lining, as there shown. This provides for completely burying the lining-engaging part of the screw in the latter. This latter-described lining-fastening and that shown in Fig. 1 are the preferable ones, for the reason that they provide for easily renewing parts of worn-out linings with new and they do not protrude inconveniently below the runway.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States,.is-

l. In a tubular metallic trolley-track having separated parallel runways, non-metallic sound-deadening linings applied to said runways, and means for fixing said linings thereto, presenting no part thereof on the wheelengaging surface thereof, substantially as described. 'r

2. In a tubular metallic trolley-track having separated parallel runways, sound-deadening linings of wood applied to said runways, and bolts fixing said linings therein having the heads thereofburied within said linings out of contact by a wheel running thereon, substantially as described.

AZRO A. COBURN. Witnesses:

II. A. CHANN, K. I. CLnMoNs. 

